


Baggage

by UnfortunatelyObsessed



Category: Supernatural
Genre: Alpha Dean Winchester, Alpha/Beta/Omega Dynamics, Crack, Fluff, M/M, Omega Castiel (Supernatural), Plot What Plot/Porn Without Plot, Sex Education, Smut, So much smut
Language: English
Status: Completed
Published: 2019-11-30
Updated: 2019-11-30
Packaged: 2021-02-25 23:46:43
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,154
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21614041
Author URL: https://archiveofourown.org/users/UnfortunatelyObsessed/pseuds/UnfortunatelyObsessed
Summary: Castiel is failing sex ed ("It's actually called Dynamic Physiology, and-") and Dean has to help him study.
Relationships: Castiel/Dean Winchester
Comments: 14
Kudos: 314





	Baggage

**Author's Note:**

  * For [itricky](https://archiveofourown.org/users/itricky/gifts).



> Prompt: Dean and Castiel best friends have to sit next to each other through sex Ed. Can you make Castiel a super sheltered omega with a crush on dean that he doesn’t think is reciprocated. Bonus points is dean says something to the effect of “so when you get knocked up Cas your gonna grow tits”

"Hey Cas."

Castiel focused on his paper.

"Cas."

He gritted his teeth.

"Caaaaaaaasssss!"

_ "What, Dean?!" _ Castiel hissed, the sound echoing across the lecture hall.

"You're gonna grow tits when you get knocked up."

"Well at least  _ my _ dick doesn't have to anchor itself inside something just to get off!" Castiel returned, voice full of snark and frustration.

"No, Cas, goddammit…" Dean mumbled, sliding a hand across his face. "We  _ studied _ this. Alphas can still get off, with or without having our knots inside someone."

Castiel opened his book to check and closed it in resignation. "Dammit."

"I don't think this is working," Dean told him, stealing his notes and beginning to fold a paper airplane. "You're not good enough at insults for this to be a good way to learn."

Castiel frowned, leaning back in his chair. "Having my insults corrected is horrifyingly embarrassing. I doubt I'll forget this again."

Dean held his hands up. "Hey man, whatever grows your tits."

Castiel scowled. "I know that one is false."

"Er, it's true."

Cas narrowed his eyes. "There is no way."

"Yeah man. Little tits. Breastfeed the pups with 'em." Dean took in Castiel's red face, contrasting sharply with his blue sweater vest. "Dude, how do you not already know this stuff? Didn't you ever just... fuck around?"

"No!" Castiel squeaked. He cleared his throat, trying again. "Um, no. I didn't. I was taught it was wrong."

Dean made a motion with his hand. "And look at ya now: failing sex ed."

"It's called Dynamic Physiology, and it's—"

"It's sex ed. I call 'em like I see 'em."

Cas huffed, rummaging through his book bag for a pen.

Dean grabbed the bag and held it beyond reach, grinning in a way that Castiel refused to admit drove him mad. "C'mon, Cassie," Dean teased. "You've never wondered what it felt like?"

"Dean—"

"To just—" Dean mimed thrusting his hips, wiggling them with a crass grin, "let an alpha take you?"

Castiel glared, even as the red on his face became less from embarrassment and more from the damned gyrating of lithe hips. "Why, have  _ you?" _ he snapped.

Dean pressed the book bag to his crotch, fake-fucking it and grinning wide at the ceiling. "Oh, yeah. Plenty of times."

Cas's brain short-circuited. "I— what? But you're a… you're an…"

"An alpha? Yeah, I know." Dean tossed a wink at him. "Doesn't mean I can't fantasize."

_ "Mr. Winchester!" _ came a sharp voice from the front of the room.

Dean's ministrations stuttered to a halt. He gulped. "Uh, yes?"

"If you're very done  _ consummating _ that book bag, we could start the lesson?"

Dean cleared his throat, tossing the bag back at Castiel's feet. "I— I'm done. Sorry, professor."

"Done?" Castiel asked him innocently, seizing the moment. "But you haven't knotted yet."

The sound Dean made was somewhere between a choke and a laugh, and no sooner had he turned joyous eyes to Castiel than they were cast out of the classroom.

They giggled freely out in the breezeway, no one around save a few students working on research projects, no doubt.

"You ass," Dean told Castiel with no real bite to the words. His eyes were shining with poorly-concealed mirth.

"I finally won a round," Cas informed him, making a tally mark in the air. "That is Castiel: One."

Dean shook his head, still laughing softly. "What now?"

Castiel, high on the haze of actually winning, remarked, "I mean, you could finish fucking my book bag."

Dean snorted, quickly covering his mouth to muffle his laughter.

"It's hard for you, Dean," Castiel deadpanned, 90% sure he was using that expression correctly.

Judging from the shaking of Dean's shoulders, he was.

"Do you need assistance?" Castiel asked, schooling his grin. "Perhaps I can alleviate the sheer amount of trouble you seem to be having."

Truthfully, Castiel planned to drag his bag up Dean's leg to about his knee and stop. Just enough to get the joke across. But Dean's head was thrown back with laughter, loud enough that the researchers had cleared. The light caught his freckles so perfectly that Castiel found himself staring, lost for anything else.

So their shock was equal when Castiel dragged the book bag directly against Dean's crotch.

Dean's eyes snapped to his, wide and a smidge blown. His laughter had stopped; instead, his lips were hanging open, plush and inviting.

Neither said a word.

Castiel cleared his throat awkwardly. "Well, Winchester?" he tried in an attempt to salvage the situation. "You gonna—" Castiel pushed the bag against Dean roughly, "— fuck this thing or what?"

They stared at each other longer, Castiel now in the awkward position of pressing his own belongings firmly against Dean's clothed dick.

Well. Fuck.

When Castiel licked his lips nervously, Dean seemed to snap back. "Yep," he said simply, stealing the bag and running away.

Castiel didn't have the presence of mind to chase him, so he didn't.

If Dean wanted to fuck his book bag then… fine. That was fine.

It wasn't  _ Castiel's _ fault that he couldn't think of anything except Dean the rest of the afternoon.

\---

"Pick up, damn you," Castiel mumbled to his phone, listening as it rang through.

_ Hey this is Dean. Leave a message at the— _

Castiel growled as he hung up, opening their texts again to see how long it had been.

Oh.

Oh,  _ fuck _ no.

Dean had left him on read.

Castiel swung open his apartment door, stalking down the hall to Dean's and knocking hard.

"Who is it?" came the voice from inside.

"Give me back my books!" Castiel yelled. "I have to study!"

"Come back tomorrow!"

"I need them  _ now!" _

"Well  _ I'm _ using them!"

Castiel hit the door again. "Use your own!"

"You know as well as I do that I never bought any!"

Cas snarled, reaching in his pocket and pulling out his wallet. A small lockpicking set was tucked neatly in it, which he made full use of now.

There was a soft  _ click, _ and Castiel swung open Dean's door. "Give me back my—" Castiel cut himself off, eyes wide.

Dean shot him with a nerf gun, sweat gleaming across his skin. "Get out, fuckwad!"

"You don't have any clothes on."

Dean shot him again. "Like I said! Get out!"

"It's warm in here. Are you sick?"

"Yes! Fine! I'm sick, so  _ get out!" _

"You're lying." Castiel furrowed his brow, taking a step closer. "What's wrong?"

Dean shot him three times in quick succession, one dart suctioning to Castiel's neck. "What's wrong? What's  _ wrong?! _ You sent me into fucking  _ rut _ is what's wrong!" Dean yelled in frustration, chest heaving.

Castiel's mind whirled. "What? No I didn't! That's not a thing! I'm not in heat!"

_ "Hence _ the books!"

"I thought rut was supposed to be—"

"You and me both, pal!" Dean fell back, hands covering his face. "All the fun parts are gone, and I'm just laying here feeling like I'm gonna go insane."

"Maybe I could—"

"Castiel I swear to fucking god, if you finish that sentence with the word 'help' I will personally dismember you."

Castiel threw out his hands in confusion. "All I said was you could fuck my book bag! That's not a sexy phrase!"

Dean curled in on himself. "Dear god make it stop."

"Did you seriously want to fuck my book bag?!"

Dean pushed himself up, eyes wild. "Castiel. Stop saying the word 'fuck' or I am going to go insane."

"Fuc— what? Why?"

"Your lips saying that word are too much for any mortal man to handle. I am a mortal man.  _ Please _ stop saying fuck."

Castiel took in the scene. Dean's body, contorted to face him; flawless skin stretching on for miles, taunting him; his book bag, laying by Dean's head.

"You were scenting my book bag," Cas realized. "You took it to hide yourself, and now you're scenting it."

Dean's eyes were begging with Castiel, pleading for all they were worth.

"You want to fuck me," Castiel concluded, wide-eyed.

A low growl escaped Dean's throat before he managed to hide his face in the canvas fabric.

Something else was moving Castiel, causing him to drop down, to crawl over to Dean. "I'm right, aren't I?" he prompted. "You want to  _ fuck _ me. You want to teach me all this sex education first hand."

"Cas," Dean gasped, doing everything in his power to keep himself sane.

"I'll tell you a secret," Castiel whispered against his ear, straddling him.

Dean bit his own bottom lip in desperation.

"I want you to fuck me, too," Castiel finished.

Dean whined low.

"You know more," Castiel drawled. "Tell me what to do."

"C'mon man," Dean groaned. "This isn't funny. I'm sufferin' here."

"What makes you think I'm joking?"

Dean's face was red, breath erratic as he tried to focus on anything but Castiel. "I know you are. This is literally word for word from a pretty popular porno."

"I'm n—" Castiel stopped talking suddenly, nostrils flaring and eyes widening.

"Cas?"

Castiel stared down at him with terror-stricken eyes for a moment. "Oh," he whispered. "Oh, you  _ ass!" _

Before Dean could react, Castiel had run out of the room, down the hall, to his own room.

Dean thunked his head back, trying to figure out what the hell had just happened.

\---

Castiel locked himself in his own room, breathing hard. He quickly stripped off his own pants and boxers, staring at them.

Fuck Dean.

_ Fuck _ Dean!

He cursed under his breath and found a few blankets to nest in for the next few days.

Damn alphas triggering his damn heat…

The thought of Dean came back to him, naked and writhing on the floor, pinned between his legs, freckles bright across an expanse of red…

With a low moan, Castiel settled himself in for the night.

\---

Dean really had only stolen the book bag to hide his boner. Really.

At least, that's what he kept telling himself.

But there was a spot that rubbed against Castiel's neck, a spot that smelled so entirely  _ him _ that it drowned the rest of the world out.

So if he buried his face in it as he got himself off, growing increasingly frustrated, then who needed to know?

\---

It was a haze of lust, Cas was sure.

He wasn't in his right mind, clouded with unfulfilling handjobs by himself. Some part of his brain, still trying to be useful, decided he needed to study.

But in order to study, he needed his books.

Which is how he wound up at Dean's door, knocking hard.

"Not a good time," came the muffled voice within.

"I need my damn books," Castiel responded, voice hoarse.

_ "Definitely _ not a good time."

Castiel growled and easily lockpicked the door.

The wall of  _ scent _ hit him like a ton of bricks.

Deep woods and pinecones and fire and amber.

Castiel had thought he understood. Really, he did. He had read about heats and ruts and everything else, and his basic knowledge was pretty good.

However, that did nothing to prepare him for the keening noise that escaped his throat.

"Damn you," Dean gritted out, quickly covering himself with the bed cover. "Give me that damn lockpick. You can't have it anymore."

Castiel looked at the tools in his hands, then back up at Dean. "Come and take them from me."

Dean covered his face for a moment before looking back up. "What do you want? Why are you here?"

And the part of his brain that was truthfully just trying to help said, "I want you to teach me about my body."

Dean let out a strangled noise.

"You put me into heat," he continued, as if that fact wasn't enough to make Dean's heart skip a beat. "I can't feel my fingertips right now, in fact, because I'm so terribly gone for you, Dean Winchester."

"You… want me?" Dean asked, shocked.

"Of course. I always have." Castiel was sweating. It was taking every last bit of his control to not rip his own clothes off and present himself ass-first. The sheer intensity of his feelings was both terrifying and exciting.

"I… want you, too."

"Well, then," Castiel began, stepping up to the edge of the bed. "Why don't we wait out our respective cycles together?"

Dean could smell Castiel clearly now. Sage and citrus and cedar and grapefruit. "Bite me," Dean said.

Castiel paused. "Was that a jab or are you asking me to—"

Dean pulled Castiel on top of him, burying his nose in the crook of his neck. "Bite me," he repeated, dragging his tongue across Castiel's neck. "And no fuckin' quips about that being an alpha thing. I'm allowed to have kinks."

Castiel shivered at the command, something deep within him growing hotter by the minute. "Good," Cas mumbled against Dean's throat, letting his teeth tease until they were scraping gently at his scent. "Because I think I have one, too."

"What's that?" Dean mumbled distractedly, hands toying with the edge of Castiel's sweater vest.

"I like when you tell me what to do," Castiel growled before sinking his teeth into Dean's scent.

Dean made a noise Castiel had never heard before. It was whining and deep and beautiful.  _ "Castiel!" _ he admonished breathily, hand grasping at Cas's hair but making no effort to pull him off. "That was a mating bite!"

Cas looked at the mark he had left, gently running his tongue over it. "Is there a difference?"

"Is there a—?" Dean groaned, leaning his head back. "You just claimed me. As your mate."

"Mmm," Cas hummed distractedly, deciding it was far more urgent to learn the tastes of Dean's chest.

Dean squirmed slightly, mind hazy. "Your life mate."

"You asked me to," Castiel mumbled distractedly, sticking his tongue out to circle around Dean's nipple.

Dean arched his back, gasping softly. "Not there I didn't! Oh, god… don't stop…"

"Hey."

"Huh?"

"Aren't  _ you _ the alpha?"

"I am?" Dean snapped back to himself. "I am!" He flipped them easily, pinning Castiel down to the bed. "And now you're getting your payback."

"My—"

Castiel was cut off by Dean's teeth sinking into his scent. He moaned, eyes rolling back and mouth falling open.

"Now we're even," Dean growled into his skin, dragging his tongue along the bite. "Mine," he said low, pulling Castiel's vest off. "I want you." He pulled the undershirt off next, pausing to admire the broad chest. "I've wanted you for so long."

The bite was doing something to Castiel. Or maybe it was Dean's heady scent. Either way, Castiel found himself whining, pulling Dean's hands onto his chest. "Want you, too… want you so bad…"

"Do you know how hard it is to pay attention in class?" Dean leaned down to press sucking kisses across Castiel's chest. "With  _ you _ beside me? With this hair?" Dean pulled Cas's hair back, exposing his throat. "Practically  _ begging _ to be fucked?"

"Fuck me," Castiel begged.

Dean's breath caught in his throat. "What did we agree on about you and that word?" he asked slowly.

Castiel met his eyes in a challenge, fiery and aroused. "Fuck. Me." He leaned up to bite Dean's ear just on the right side of rough. "Or else I'm going to fuck  _ you." _ Castiel's hands were travelling down. "You'd like that, wouldn't you? I'd pretend to be your alpha, and you'd come undone under me."

Dean caught Cas's hands and pinned them to the bed above him, face red, breathing hard. "God yes," Dean gasped out. "But not tonight. Stay." Dean let go of his hands, making sure he stayed put before undoing Castiel's jeans and sliding them off in one go.

He pulled the boxers down too, and had to lean his head into the curly hair above Cas's dick for a moment to regain himself from the sweet smell of Cas's slick.

"Are you going to take me or what?" Cas drawled.

Dean chuckled softly, even as he slid up Castiel's body, tucking his hands under his knees. "The mouth on this one," he mused.

"Put it to use," Castiel challenged, canting his hips up to grind against Dean.

"Ohhh fuck," Dean groaned out, bracing his arms on either side of Cas. "You're gonna be the death of me."

They stared into each other's eyes, breathing hard, before Cas asked quietly, "Kiss me?"

And Dean kissed Castiel deeply and harshly, tongue sliding in with just as much ease as his roaming fingers did elsewhere.

Castiel gasped and moaned into Dean's mouth, legs coming up to circle his waist.

Dean's free hand was exploring every inch of the body he had always admired from afar, until Castiel was ready, wet and frustrated.

"Ready for me?" Dean whispered, kissing down his chin, his neck.

"Yes, please," Castiel panted back, mind fuzzy. "Take me, god, take me."

Dean slid home, biting again at Castiel's mating mark, causing him to arch up under him.

Dean wrapped an arm around him, letting him settle before pulling out and back in.

Castiel's hands had long since moved from their spot, scrabbling against Dean's back as he breathed and moaned into Dean's neck.

Dean's pace was slow and unbearably forgiving, until Castiel sucked harshly against his scent and growled, "I said,  _ take me." _

Dean whined softly before hammering into Castiel with every bit of energy he had left.

He was relentless, dick a literal fucking machine, and he wasn't going to last long if Castiel kept making those porn-worthy noises right in his ear.

His will ran out when he angled just right to hit Castiel's prostate, and Castiel turned his head away and screamed,  _ "Fuck!" _

Dean came undone.

Spurt after spurt of cum pistoned out of him, and he tried to pull back before his knot fully formed but Castiel's legs stopped him.

"Cas—"

"Please," Cas whispered, eyes squeezed shut and muscles vibrating.

Dean reached between them and took hold of Castiel's dick, watching in awe at the bliss that began blooming on Castiel's face.

He twisted his wrist at the base, coming back up, using precome to smooth the way.

His knot was filling Castiel, forcing them together for the next however long.

"C'mon baby," Dean found his lips saying. "I've got you. You can let go. I've got you." He pushed his dick in, as little left as it could possibly go, and bent down to suck a mark onto Castiel's neck.

With a strangled noise, Castiel was cumming between them.

Dean jacked him through it, whispering praises and sweet everythings until Castiel came down with a sigh.

His eyes remained closed for a while before he finally looked at Dean.

"Hey, beautiful," Dean whispered.

Castiel laughed softly. "Hello."

"We're gonna be here a while."

"That I do remember," Cas chuckled.

Dean relaxed on top of him to wait his knot out, burrowing his nose into Castiel's neck. "Hey, babe?"

"Hmm?"

"We missed the final."

Cas's eyes flew open. "Son of a—"


End file.
